Icom iC- r8500, Service Manual Addendum

Page: 110 / 286

5 - 3
5-3 RECEIVER ADJUSTMENT
ADJUSTMENT ADJUSTMENT CONDITIONS
MEASUREMENT
VALUE
ADJUSTMENT
POINT
UNIT LOCATION UNIT ADJUST
PIN ATT 1 • Frequency : 14.10000 MHz
• Mode : USB
• Receiving
RF-C Connect a digital
multimeter to CP1. 1.7 V RF-C R63
HF
SENSITIVITY 1 • Frequency : 14.09850 MHz
• Mode : USB
• [10dB] : ON
• [AGC] : Fast
• Connect an SSG to the antenna connector
for 0.1–30 MHz (50
Ω
ANT) and set as;
Frequency : 14.10000 MHz
Level* : 0.56 µV (–112 dBm)
Modulation : OFF
• Receiving
Rear
panel
C o n n e c t a n A C
voltmeter to the [EXT
SP] with an 8
Ω
load.
Maximum output
level
Adjust in
sequence
L65, L66,
L63, L62
repeatedly
2 • Set the SSG as;
Level
: OFF
• Receiving
Minimum output
level
R77
1ST MIXER
BIAS
VOLTAGE 1 • Frequency : 173.00000 MHz
• Disconnect J4.
• Receiving
RF-D Connect a digital
multimeter to both
sides of R91. 0.2 V RF-D R109
HPF SHIFT
VOLTAGE 1 • Frequency : 1300.00000 MHz
• Mode : FM
• Receiving
CONV-B Connect a digital
multimeter to CP2. 14.5 V CONV-B R55
2 • Frequency : 1100.00000 MHz
• Receiving
2.0–4.0 V Verify
NOTE: Before adjusting WFM SENSITIVITY, 5-4 RF-C BPF TUNED VOLTAGE must be adjusted.
SENSITIVITY
(WFM) 1 • Frequency : 173.02000 MHz
• Mode : WFM
• Connect an SSG to the antenna connector
for 30–2000 MHz and set as;
Frequency : 173.02000 MHz
Level* : 3.2 µV (–97 dBm)
Modulation : 1 kHz
Deviation : ±75 kHz
• Receiving
MAIN-A Connect a digital
multimeter to CP4. Minimum
level
(Note the voltage
as the reference)
MAIN-A Adjust in
sequence
L7, L8, L9,
L10
repeatedly
(FM) 2 • Frequency : 173.02000 MHz
• Mode : FM
• Connect an SSG to the antenna connector
for 30–2000 MHz and set as;
Frequency : 173.02000 MHz
Level* : 3.2 µV (–97 dBm)
Modulation : 1 kHz
Deviation : ±5 kHz
• Receiving
Front
panel
S-meter Maximum
level
MAIN-A Adjust in
sequence
L14, L17,
L22, L25,
L26
repeatedly
3 • Set the SSG as;
Level*
: 32 µV (–77 dBm)
Modulation : None
MAIN-A Connect a digital
multimeter to CP5. The same voltage
on " SENSITIVITY
(WFM)." MAIN-A R60
4 • Set the SSG as;
Level
: OFF
Front
panel
The center
indicator
disappears.
1ST IF
NOTCH 1 • Frequency : 788.60000 MHz
• Mode : FM
• Connect an SSG to the antenna connector
for 30–2000 MHz and set as;
Frequency : 810.00000 MHz
Level* : 32 mV (–17 dBm)
Modulation : 1 kHz
Deviation : ±75 kHz
• Receiving
Front
panel
S-meter Maximum
level
MIX-A L15
*; This output level of the SSG is indicated as SSG's terminated circuit.
RECV
AFC
Center indicator
(Replacement page)
Apr. 2010